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  <title>OverFlow</title>
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        body {
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        main {
            background: #9b59b6;
            height: 100px;
            padding: 20px;
            box-sizing: border-box;
        }

        span {
            background: #e67e22;
            display: inline-block;
            width: -webkit-fill-available;
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        houdunren.com
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